Reorganize source files

include/beast/websocket/detail/utf8_checker.hpp

@@ -0,0 +1,172 @@
+//
+// Copyright (c) 2013-2016 Vinnie Falco (vinnie dot falco at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef BEAST_WEBSOCKET_DETAIL_UTF8_CHECKER_HPP
+#define BEAST_WEBSOCKET_DETAIL_UTF8_CHECKER_HPP
+
+#include <boost/asio/buffer.hpp>
+#include <cstdint>
+#include <string> // DEPRECATED
+
+namespace beast {
+namespace websocket {
+namespace detail {
+
+// Code adapted from
+// http://bjoern.hoehrmann.de/utf-8/decoder/dfa/
+/*
+    Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
+
+    Permission is hereby granted, free of charge, to any person obtaining
+    a copy of this software and associated documentation files (the
+    "Software"), to deal in the Software without restriction, including
+    without limitation the rights to use, copy, modify, merge, publish,
+    distribute, sublicense, and/or sell copies of the Software, and to
+    permit persons to whom the Software is furnished to do so, subject
+    to the following conditions:
+
+    The above copyright notice and this permission notice shall be included
+    in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+    OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
+    ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
+*/
+template<class = void>
+class utf8_checker_t
+{
+    // Table for the UTF8 decode state machine
+    using lut_type = std::uint8_t[400];
+    static
+    lut_type const&
+    lut()
+    {
+        // 400 elements
+        static std::uint8_t constexpr tab[] = {
+            0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 00..1f
+            0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 20..3f
+            0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 40..5f
+            0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 60..7f
+            1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, // 80..9f
+            7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, // a0..bf
+            8,8,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, // c0..df
+            0xa,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x4,0x3,0x3, // e0..ef
+            0xb,0x6,0x6,0x6,0x5,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8, // f0..ff
+            0x0,0x1,0x2,0x3,0x5,0x8,0x7,0x1,0x1,0x1,0x4,0x6,0x1,0x1,0x1,0x1, // s0..s0
+            1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,1, // s1..s2
+            1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1, // s3..s4
+            1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,3,1,3,1,1,1,1,1,1, // s5..s6
+            1,3,1,1,1,1,1,3,1,3,1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,1,1,1,1,1  // s7..s8
+        };
+        return tab;
+    }
+
+    std::uint32_t state_ = 0;
+    std::uint32_t codepoint_ = 0;
+
+public:
+    utf8_checker_t() = default;
+    utf8_checker_t(utf8_checker_t&&) = default;
+    utf8_checker_t(utf8_checker_t const&) = default;
+    utf8_checker_t& operator=(utf8_checker_t&&) = default;
+    utf8_checker_t& operator=(utf8_checker_t const&) = default;
+
+    void
+    reset();
+
+    // Returns `true` on success
+    bool
+    write(void const* buffer, std::size_t size);
+
+    // Returns `true` on success
+    template<class BufferSequence>
+    bool
+    write(BufferSequence const& bs);
+
+    // Returns `true` on success
+    bool
+    finish();
+};
+
+template<class _>
+void
+utf8_checker_t<_>::reset()
+{
+    state_ = 0;
+    codepoint_ = 0;
+}
+
+template<class _>
+bool
+utf8_checker_t<_>::write(void const* buffer, std::size_t size)
+{
+    auto p = static_cast<std::uint8_t const*>(buffer);
+    auto plut = &lut()[0];
+    while(size)
+    {
+        auto const byte = *p;
+        auto const type = plut[byte];
+        if(state_)
+            codepoint_ = (byte & 0x3fu) | (codepoint_ << 6);
+        else
+            codepoint_ = (0xff >> type) & byte;
+        state_ = plut[256 + state_ * 16 + type];
+        if(state_ == 1)
+        {
+            reset();
+            return false;
+        }
+        ++p;
+        --size;
+    }
+    return true;
+}
+
+template<class _>
+template<class BufferSequence>
+bool
+utf8_checker_t<_>::write(BufferSequence const& bs)
+{
+    using boost::asio::buffer_cast;
+    using boost::asio::buffer_size;
+    for (auto const& b : bs)
+        if(! write(buffer_cast<void const*>(b),
+                buffer_size(b)))
+            return false;
+    return true;
+}
+
+template<class _>
+bool
+utf8_checker_t<_>::finish()
+{
+    auto const success = state_ == 0;
+    reset();
+    return success;
+}
+
+using utf8_checker = utf8_checker_t<>;
+
+template<class = void>
+bool
+check_utf8(char const* p, std::size_t n)
+{
+    utf8_checker c;
+    if(! c.write(p, n))
+        return false;
+    return c.finish();
+}
+
+} // detail
+} // websocket
+} // beast
+
+#endif